<template>
  <view>
    <!-- 使用自定义的搜索组件-->
    <!-- <my-search :bgcolor="'pink'" @></my-search> -->
    <my-search  @click="gotosearch"></my-search>
    
    <view class="scroll_view_container">
      <!-- 左侧的滑动区域 -->
      <scroll-view class="left_scroll_view" scroll-y="true" :style="{height: wh + 'px'}">
        <block v-for="(item,i) in cateList" :key="i">
          <view :class="['left_scroll_view_item', i== active? 'active' : '']" @click="activechanged(i)">{{item.cat_name}}</view>
        </block>
      </scroll-view>
      <!-- 右侧的滑动区域 -->
      <scroll-view scroll-y="true" :style="{height: wh + 'px'}" :scroll-top="scrollTop">
        <view class="cate_lv2" v-for="(item2,i) in cateLevel2" :key="i">
          <view class="cate_lv2_title">
            / {{item2.cat_name}}/
          </view>
          <!-- 动态渲染三级分类的列表数据 -->
          <view class="cate_lv3_list">
            <view class="cate_lv3_item" v-for="(item3, i) in item2.children" :key="i" @click="getGoodsList(item3)">
              <!-- 图片 -->
                <image :src="item3.cat_icon.replace('dev', 'web')" mode="widthFix"></image>
              <!-- 文本 -->
                <text>{{item3.cat_name}}</text>
            </view>
          </view>
        </view>
      </scroll-view>
    </view>
  </view>
</template>

<script>
  export default {
 
    data() {
      return {
        // 当前设备可用的高度
        wh:0,
        // 分类数据的列表
        cateList:[],
        active:0,
        
        // 二级分类数据的列表
        cateLevel2:[],
        // 滚动条距离视图区域
        scrollTop:0
      };
    },
    onLoad() {
      const sysInfo = uni.getSystemInfoSync()
      this.wh = sysInfo.windowHeight - 50
      
      this.getcateList()
    },
    methods:{
     async getcateList(){
       // 发起请求
           const { data: res } = await uni.$http.get('/api/cate')
           // 判断是否获取失败
           if (res.meta.status !== 200) return uni.$showMsg()
           // 转存数据
           this.cateList = res.message
           
           // 为二级分类赋值
            this.cateLevel2 = res.message[0].children
     },
     activechanged(i){
       this.active = i
       
       // 重新为二级分类赋值
        this.cateLevel2 = this.cateList[i].children
        
        // 让scollTap 的值在0与1之间切换
        this.scrollTop = this.scrollTop ? 0: 1
     },
     
     // 点击三级分类跳转到商品列表页面
    getGoodsList(item3){
      uni.navigateTo({
        url:'/subpkg/goods_list/goods_list?cid=' + item3.cat_id
      })
    },
    gotosearch(){
      uni.navigateTo({
        url:'/subpkg/search/search'
      })
    }
     
    }
  }
</script>

<style lang="scss">
.scroll_view_container{
  display: flex;
  
  .left_scroll_view{
    width:130px;
      
    .left_scroll_view_item{
      background-color: #F7F7F7;
      line-height: 60px;
      text-align: center;
      font-size: 12px;
      
      &.active{
        background-color: #FFFFFF;  
        position: relative;
        
        &::before{
         content: '';
         display: block;
         width: 3px;
         height: 30px;
         background-color: #c00000;
         position: absolute;
         top: 50%;
         left:0;
         transform: translateY(-50%);
        }
      }
    }
  }
}

.cate_lv2_title{
  font-size: 12px;
  font-weight: bold;
  text-align:center;
  padding: 15px 0;
}

.cate_lv3_list {
  display: flex;
  flex-wrap: wrap;
  .cate_lv3_item{
    width: 33.3%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-content: center;
    margin-bottom: 10px;
    image{
      width: 60px;
      height: 60px;
    }
    text{
      font-size: 12px;
    }
  }
}

</style>
